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'Beatrix' is a phaser, offering voltage control over notch frequencies, effect depth and feedback (resonance). It also offers an unusual 'offset' control allowing you to sweep the filter notches without sweeping the resonant frequency.

Further options are provided by the 'phase' switch (which disables the phasing sound and essentially turns the module into a resonant peak filter) and 'sum' switch (which inverts the filtered signal, giving a different flavour of phasing).

Beatrix will self-oscillate at high feedback if desired, though the front panel control is factory-trimmed to stop just short of self-oscillation.

The module is 100% analogue, using discrete transistor OTAs.


Sound On Sound magazine (June 2022 issue) said

The phaser itself sounds great. It has a wide variety of character on offer within its range; from watery, swooshing phase to more of a classic, MXR Phase 90‑style sound.

Read the full review here.


Beatrix's specifications are as follows:
  • Panel width: 8HP
  • Module depth: 37mm
  • Current draw: 22mA on the +12V rail, 21mA on the -12V rail
  • Inputs:
    • Frequency (approximately 1V/octave, with attenuator)
    • Offset
    • Depth
    • Feedback
    • Audio input (with attenuator)
  • Outputs:
    • Audio output

For more detail, please see the user manual.
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Pricing & Availablity

Beatrix is available now.

MSRP: UK £159 (inc VAT), US $189 (exclusive of sales tax), EU €154.36 (exclusive of VAT)

For purchasing links, please see where to buy.

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